Early in its run How I Met Your Mother quickly proved it was a funny and clever series, and "Slutty Pumpkin" was one of the earliest examples. A sly send up of It's the Great Pumpkin, Charlie Brown, the episode establishes that every year Ted ritualistically goes to the same rooftop party, staying out there after everyone has left, in hopes of seeing the Slutty Pumpkin.

The Slutty Pumpkin is a girl Ted met at that same party years before, a girl dressed as well, you can figure it out. We never get a full look at her, making her an earlier "Could this be the Mother?" candidate, but also allowing us to fill in the blanks on what exactly a Slutty Pumpkin looks like and sending up the Slutty Pirate/Cowgirl/investment banker/astronaut/you-name-it trend that's grown among Halloween costumes in recent years.

The episode features a ton of great jokes, including Barney's ever-changing costume, starting with his awesome Top Gun uniform intro, complete with Kenny Loggins playing. He then changes into a devil costume, allowing for the brilliant sight gag of him influencing Ted to pee off the roof, while a stranger in an angel costume stands on Ted's other side, telling him not to. The coup de grace is Barney actually fooling Ted into thinking he is the Slutty Pumpkin by dressing up a penguin. If you haven't seen the episode, trust us, it makes sense (and is hysterical) in context.

The first of two brilliant but quickly cancelled teen shows on this list (Freaks and Geeks is the other) My So-Called Life proved to be unafraid to be a bit experimental in its brief time on the air. This episode, the ninth, proved they even were comfortable getting a bit supernatural on the audience, even though the show involved some very down to earth and relatable characters.

On Halloween, Angela and her friends get locked inside their high school, and for Angela, things then get a bit trippy. Whether it's something she's creating inside her own mind or actually happening, Angela is seeing a ghost, a student who went to her school decades before, only to tragically die in a prank gone wrong. Dressed as a 1960s student, Angela finds herself transported to the school as it was during that era while she talks to this long gone guy, who has more than a hint of Angela's beloved Jordan Catalano about him. It was a risky move for the show to take, going into such an odd place yet they pulled it off, and created genuine emotion in the process.

On a more comical note was Brian's increasingly slack jawed reaction to Rayanne, who was dressed up as a sexy vampire and seemed both amused and annoyed by his attention. Brian and Rayanne couldn't be more different, but this episode played them off each other in a very funny and interesting way. And lest we forget, this was the episode where Halloween costumes turned into a bit of role playing for parents Patty and Graham, who amusingly ended up quite turned on by the process of playing dress up.

This is the original in what became a tradition of clever Halloween episodes for the series. This also happens to be Season 2, arguably the best season of the show (and far, far removed from the post-lottery years). It has everything that made the show great, from Roseanne's unique parenting style, to the dynamic and bantering relationship of Roseanne and Dan, and as always, the woes of living the working class life.

We learn that, for all their problems, the Connors love Halloween; deeply and, perhaps, somewhat insanely. They commit to it, from the costumes to their home-made haunted house to Dan scaring Roseanne with a chainsaw and a hockey mask - while backlit with a flood lamp. What's fun about the episode (and even subsequent Halloween episodes) is that it feels as real as anything else in the show. The producers didn't run out and get a special effects artist to do everyone up. This is just the Connors being the Connors and one of the best arguments for what Halloween is all about and why it's so much fun to real people.